Tullow Oil, one of the Britain's most successful exploration groups, has made its first discovery in the Arctic in a move which will encourage more drilling and anger green groups campaigning against fossil fuel extraction in the region.

Shares in Tullow climbed more than 3% as well operator OMV said it had struck a reservoir in the Barents Sea off the far north of Norway which could contain up to 160m barrels of oil and 40bn cubic feet of recoverable gas.

"This is a major frontier light oil discovery for Norway, Tullow Oil and our co-venturers. We look forward to pursuing the exciting exploration and appraisal follow up arising from this breakthrough discovery," said Angus McCoss, exploration director at Tullow, which holds a 20% stake in the prospect.

"The well results are a breakthrough for the regional exploration activities as the presence of good quality oil shows the possible large potential of an area, which will see more exploration drilling in the near future," said OMV in a statement.

The Austrian company said the production licence 537 in which the well was drilled could hold as much as 500m barrels of oil equivalent based on similar geological evidence nearby.

Tullow has become a stock market favourite on the back of major discoveries in Uganda and Ghana that helped establish those African nations as new oil producers.

The company, led by Irishman Aidan Heavey, has also become the targets of various campaign groups who have accused it of political lobbying, tax avoidance and even bribery, allegations it has steadfastly denied.

But the oil strike in the far north is a significant step for Tullow, which last autumn bought a 40% stake in exploration acreage of Greenland just weeks after the boss of French oil group, Total, said drilling in the Arctic should be abandoned because of the potential reputational and environmental damage if there was an oil spill.

Greenpeace has made protection of the far north one of its key campaigns and last month its Arctic Sunrise vessel was chased out of Arctic waters by Russian coast guards after it approached a drill rig working for Moscow-based oil company, Rosneft.

Russia and Norway signed an historic agreement to carve up the Barents Sea between them in 2010, a move which was expected to herald much more drilling in the region.

The Oslo government unveiled 20 new exploration licences in the Barents during the summer and Statoil has already made big finds in the more southerly part of the Barents

Andrew Whittock, an oil analyst with Liberum Capital in London, said the Tullow find was significant although these were early days to try to assess the reservoir's ultimate potential. "This proves a new shallow play in the region. Good news but (it) needs more appraisal."